This invention relates to built detergent compositions containing tetramethylene oxide (TMO) surfactants. More particularly, this invention encompasses built detergent compositions comprising, as the surfactant, novel zwitterionic compounds characterized by a particular placement and number of TMO groups and particular hydrophobic groups. Importantly, the TMO moiety can be introduced into the instant surfactant compounds using tetrahydrofuran as a precursor. Tetrahydrofuran, in turn, is available from plant by-products such as corncobs, oat hulls, cottonseed hulls, and bagasse. To this extent, the zwitterionic surfactants used herein are not based on scarce petro-chemical feedstocks in the manner of ethylene oxide-containing detersive surfactants.
The use of zwitterionic compounds (i.e., the so-called "internally neutralized" surface active compounds having both positive and negative charge centers) in laundry detergents is known. In contrast with many prior art zwitterionic detersive surfactants, the compositions herein employ zwitterionic compounds having a TMO substituent which provides both charge separation and hydration interposed between the oppositely-charged centers of the molecule. The TMO-zwitterionics are particularly useful for removing clay and oily soils from fabrics, even in low- or non-built detergent compositions. Moreover, the use of builders in combination with the TMO-zwitterionics in the manner of the present invention allows the formulation of superior detergents at a more economical cost.